CN110741612B

CN110741612B - Configuration method of scheduling request, network equipment and terminal equipment

Info

Publication number: CN110741612B
Application number: CN201780091688.0A
Authority: CN
Inventors: 唐海
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2017-09-15
Filing date: 2017-09-15
Publication date: 2022-05-17
Anticipated expiration: 2037-09-15
Also published as: AU2017431901A1; CN110741612A; US20200280423A1; EP3684023B1; EP3684023A1; WO2019051766A1; US11582011B2; KR20200047721A; JP2020537375A

Abstract

The invention discloses a configuration method of a scheduling request, network equipment, terminal equipment and a computer storage medium, wherein the method comprises the following steps: receiving at least one bandwidth part BWP configured on the network side; receiving configuration parameters of at least one scheduling request configured for each BWP by a network side; and the configuration parameters of the scheduling request and the logical channel have a mapping relation.

Description

Configuration method of scheduling request, network equipment and terminal equipment

Technical Field

The present invention relates to the field of information processing technologies, and in particular, to a method for configuring a scheduling request, a network device, a terminal device, and a computer storage medium.

Background

The LTE Scheduling Request (SR) is a 1-bit message transmitted on the PUCCH, which is used by the terminal to request an uplink grant resource. In LTE, a MAC entity corresponding to one terminal may configure one or more SR configurations. Configuring multiple SR configurations is that in case of CA, SCell may have corresponding SR configurations. In the NR discussion, it has been agreed to configure a UE MAC entity with multiple SR configurations even in the case of a single carrier.

In addition, in NR, the supported system bandwidth is much larger than the maximum LTE 20MHz system bandwidth, for some terminals, the capability is limited, and therefore, the NR does not necessarily support the whole system bandwidth, and meanwhile, in order to improve the scheduling efficiency, the NR introduces a concept of bandwidth part (BWP: bandwidth part). BWP is a concept of a frequency domain dimension. Meanwhile, the existing discussion assumes that the terminal supports only one active BWP at one point in time. However, in such a scenario, there is a problem to be solved, that is, how to ensure that the terminal device cannot correctly transmit the SR due to a mapping relation failure when the single-carrier user device performs BWP handover.

Disclosure of Invention

To solve the foregoing technical problem, embodiments of the present invention provide a method for configuring a scheduling request, a network device, a terminal device, and a computer storage medium.

The configuration method of the scheduling request provided by the embodiment of the invention is applied to terminal equipment, and comprises the following steps:

receiving at least one bandwidth part BWP configured on the network side;

receiving configuration parameters of at least one scheduling request configured for each BWP by a network side; and the configuration parameters of the scheduling request and the logical channel have a mapping relation.

The configuration method of the scheduling request provided by the embodiment of the invention is applied to network equipment, and comprises the following steps:

configuring at least one bandwidth part BWP for the terminal device;

configuring configuration parameters of at least one scheduling request for each of the at least one BWP; and the configuration parameters of the scheduling request and the logical channel have a mapping relation.

The terminal device provided by the embodiment of the invention comprises:

a first receiving unit, configured to receive at least one bandwidth part BWP configured on the network side;

a second receiving unit, configured to receive configuration parameters of at least one scheduling request configured for each BWP by the network side; and the configuration parameters of the scheduling request and the logical channel have a mapping relation.

The network device provided by the embodiment of the invention comprises:

a first configuration unit configured to configure at least one bandwidth part BWP for the terminal device;

a second configuration unit, configured to configure configuration parameters of at least one scheduling request for each BWP of the at least one BWP; and the configuration parameters of the scheduling request and the logical channel have a mapping relation.

An embodiment of the present invention provides a network device, including: a processor and a memory for storing a computer program capable of running on the processor,

wherein the processor is configured to perform the steps of the aforementioned method when running the computer program.

An embodiment of the present invention provides a terminal device, including: a processor and a memory for storing a computer program capable of running on the processor,

Embodiments of the present invention provide computer storage media having computer-executable instructions stored thereon that, when executed, perform the steps of the aforementioned methods.

According to the technical scheme of the embodiment of the invention, a plurality of BWPs configured for a terminal device by a network can be received, configuration parameters of a plurality of corresponding scheduling requests can be configured in each BWP, and a mapping relation is provided between the configuration parameters of each scheduling request and a logical channel. Therefore, the problem that the SR cannot be correctly sent due to the failure of the mapping relation when the terminal device switches the BWP can be avoided, and the processing efficiency of the system is ensured.

Drawings

Fig. 1 is a schematic flowchart of a method for configuring a scheduling request according to an embodiment of the present invention 1;

fig. 2 is a schematic flowchart of a method for configuring a scheduling request according to an embodiment of the present invention, which is shown in fig. 2;

fig. 3 is a schematic flowchart of a method for configuring a scheduling request according to an embodiment of the present invention, which is shown in fig. 3;

FIG. 4 is a schematic diagram of a structure of a terminal device according to an embodiment of the present invention;

FIG. 5 is a schematic diagram of a network device according to an embodiment of the present invention;

fig. 6 is a schematic diagram of a hardware architecture according to an embodiment of the present invention.

Detailed Description

So that the manner in which the features and aspects of the embodiments of the present invention can be understood in detail, a more particular description of the embodiments of the invention, briefly summarized above, may be had by reference to the embodiments, some of which are illustrated in the appended drawings.

The first embodiment,

The present application provides a method for configuring a scheduling request, which is applied to a terminal device, as shown in fig. 1, and includes:

step 101: receiving at least one BWP configured on a network side;

step 102: receiving configuration parameters of at least one scheduling request configured for each BWP by a network side; and the configuration parameters of the scheduling request and the logical channel have a mapping relation.

Here, the BWP is a concept of a frequency domain dimension, specifically, one or more BWPs that can be configured for a terminal at the network side (or a specific network device) in the RRC connected state; the BWP may mainly include the following three parameters: numeriology: marking a basic parameter set and marking a carrier spacing SCS; a center frequency point and a bandwidth. Wherein the size of the bandwidth is less than or equal to the maximum system bandwidth.

The at least one BWP configured on the network side may be one or more, for example, two or three BWPs, that is, the terminal device may switch among several BWPs.

The Configuration parameters (SR Configuration) of the scheduling request may include parameters such as time domain resources, frequency domain resources, and the number of times of transmission of the request;

for example, the configuration of RRC signaling for each SR configuration is as follows:

wherein SR-PUCCH-resource index indicates the frequency domain resource of the SR transmitted by the UE, and the following description shows that the field is an integer and the value range is 0-2047; the SR-ConfigIndex indicates the time domain resource of PUCCH for transmitting SR, the value of the resource is an integer and the range is 0-157; the dsr-TransMax determines the maximum number of SR transmissions.

It should be noted that there may be no sequence between the

foregoing steps

101 and 102, that is, the step 101 may be executed while the step 102 is executed.

Specifically, after the terminal device completes step 101 and step 102, a plurality of BWPs configured by the network and Configuration parameters (SR Configuration) of at least one scheduling request corresponding to each BWP may be obtained; in addition, each SR Configuration can correspond to one or more logical channels. It is further noted that each logical channel may correspond to at most one SR Configuration.

For example, referring to table 1, for SR configurations belonging to different BWPs, the network configures mapping relationships between logical channels and these SR configurations in advance, for example, BWP- ｃA has two SR configurations, BWP-B has three SR configurations, and BWP-C has one SR configuration:

Logical Channel	BWP-A	BWP-B	BWP-C
				LCH1	SR-CONFIG-A-i	SR-CONFIG-B-i	SR-CONFIG-C-i
LCH2	SR-CONFIG-A-i	SR-CONFIG-B-ii	SR-CONFIG-C-i
				LCH3	SR-CONFIG-A-ii	SR-CONFIG-B-iii	SR-CONFIG-C-i

TABLE 1

After the foregoing steps are completed, on the basis of the flow provided in fig. 1, this embodiment may further include, as shown in fig. 2: step 103: receiving BWP activation information sent by a network side;

wherein the BWP activation information is used to deactivate a first BWP currently used by the terminal device and activate a second BWP of at least one BWP configured to the terminal device; the first BWP is different from the second BWP.

Taking table 1 as an example, when the terminal receives the BWP activation instruction, the mapping relationship between the preconfigured logical channel and the SR configuration is adopted according to whether the activated BWP belongs to BWP- ｃA, BWP-B or BWP-C.

As can be seen from the foregoing steps, before step 103 is executed, that is, before the BWP activation information sent by the network side is received, the terminal device can acquire all configuration relationships as shown in table 1, that is, the terminal device can acquire the mapping relationship between the logical channel and the configuration parameters of the scheduling request and the mapping relationship between the configuration parameters of the scheduling request and the BWP in advance.

Further, as shown in fig. 2, after completing step 103, the method may further include:

step 104: determining configuration parameters of a scheduling request corresponding to a second BWP based on configuration parameters of the second BWP indicated to be activated in the BWP activation information and at least one scheduling request configured for each BWP;

step 105: and determining a logical channel corresponding to the configuration parameters of the scheduling request of the second BWP based on the configuration parameters of the scheduling request of the second BWP.

That is, when receiving a bandwidth segment (BWP) activation command, the terminal changes the mapping relationship between the logical channel and the SR configuration according to the activation information or the RRC configuration information, and when transmitting the SR, the terminal transmits the SR using the updated mapping relationship.

According to the foregoing embodiments, it can be seen that the terminal device is configured with a plurality of BWPs, and for a certain BWP, a plurality of SR configurations are configured; for a certain active BWP, the network configures the terminal with a mapping relationship from the logical channel to the SR configuration, where the active BWP is the BWP where the terminal transmits and receives data at the current time.

Further, regarding the mapping relationship between the logical channel and the SR configuration, as shown in table 2, for example, the terminal has logical channels LCH1, LCH2, LCH 3; SR-CONFIG a, SR-CONFIG b:

LCH1	SR-CONFIG a
		LCH2	SR-CONFIG a
LCH3	SR-CONFIG b

TABLE 2

The terminal receives the BWP activation command, and deactivates (deactivate) the current BWP (i.e. the first BWP) by instructing the terminal to activate another BWP (i.e. the second BWP), the another BWP being instructed by the activation command; meanwhile, through a BWP activation instruction, the terminal updates the mapping relation between the logical channel and the new SR configuration, and the new SR configuration belongs to the new BWP which is activated according to the activation instruction indication; the updating modes include the following three modes: pre-configuration, RRC dedicated signaling change, and one SR configuration.

Further, after determining the logical channel corresponding to the configuration parameter of the scheduling request of the second BWP based on the configuration parameter of the scheduling request of the second BWP, the method further includes:

when the logical channel triggers the SR to report, selecting a resource of a corresponding physical uplink channel based on a configuration parameter of a scheduling request mapped by the logical channel corresponding to the second BWP, and sending the SR on the selected resource of the physical uplink channel.

And the terminal equipment selects the corresponding PUCCH resource to transmit the SR by adopting the mapped SR configuration when one logic channel triggers SR reporting based on the mapping relation between the logic channel and the SR configuration.

It can be seen that, by adopting the above-mentioned scheme, multiple BWPs configured by the network for the terminal device can be received, and configuration parameters of multiple corresponding scheduling requests can be configured in each BWP, and a mapping relationship is provided between the configuration parameters of each scheduling request and the logical channel. Therefore, the problem that the terminal device cannot correctly send the SR due to the failure of the mapping relation when switching the BWP can be avoided, and the processing efficiency of the system is ensured.

Example II,

The present application provides a method for configuring a scheduling request, which is applied to a network device, as shown in fig. 3, and includes:

step 301: configuring at least one bandwidth part BWP for the terminal device;

step 302: configuring configuration parameters of at least one scheduling request for each of the at least one BWP; and the configuration parameters of the scheduling request and the logical channel have a mapping relation.

Here, BWP is a concept of a frequency domain dimension, specifically, one or more BWPs that can be configured to the terminal in the RRC connected state on the network side (or a specific network device); the BWP may mainly include the following three parameters: numeriology: marking a basic parameter set and marking a carrier spacing SCS; a center frequency point and a bandwidth. Wherein the size of the bandwidth is less than or equal to the maximum system bandwidth.

It should be noted that there may be no sequence between the foregoing step 301 and step 302, that is, step 302 may be executed while step 301 is executed.

Specifically, after the terminal device completes step 301 and step 302, a plurality of BWPs that can be configured for the terminal device and Configuration parameters (SR Configuration) of at least one scheduling request corresponding to each BWP; in addition, each SR Configuration can correspond to one or more logical channels. Further, each logical channel may correspond to at most one SR Configuration.

For example, referring to table 1, when the network configures BWP for the terminal, the mapping relationship between SR configuration and LCH in BWP is configured in advance; such as:

the network configures three kinds of BWP, BWP-A, BWP-B and BWP-C for the terminal;

for SR configurations belonging to different BWPs, the network pre-configures mapping relationships between logical channels and these SR configurations, for example, BWP- ｃA has two SR configurations, BWP-B has three SR configurations, and BWP-C has one SR configuration:

TABLE 1

After the foregoing steps are completed, the method further includes: sending BWP activation information to the terminal device;

As can be seen from the foregoing steps, before sending the BWP activation information, the terminal device can acquire all the configuration relationships shown in table 1, that is, the terminal device can acquire the mapping relationship between the logical channel and the configuration parameters of the scheduling request and the mapping relationship between the configuration parameters of the scheduling request and the BWP in advance.

Further, the sending BWP activation information to the terminal device includes one of:

sending BWP activation information to the terminal equipment through a Radio Resource Control (RRC) dedicated configuration signaling;

sending BWP activation information to the terminal equipment through Downlink Control Information (DCI);

transmitting, by a Control Element (CE) of a Media Access Control (MAC) layer, BWP activation information to the terminal device;

and sending the BWP activation information to the terminal equipment through a preset information format.

Accordingly, after the transmission of the activation information is completed, the terminal device can select a corresponding PUCCH resource to transmit an SR by using the mapped SR configuration when a certain logical channel triggers SR reporting based on the mapping relationship between the logical channel and the SR configuration.

Example III,

The present application provides a terminal device, as shown in fig. 4, including:

a first receiving unit 41, configured to receive at least one bandwidth part BWP configured on the network side;

a second receiving unit 42, configured to receive configuration parameters of at least one scheduling request configured for each BWP by the network side; and the configuration parameters of the scheduling request and the logical channel have a mapping relation.

Specifically, after the foregoing function is completed, a plurality of BWPs configured by the network and Configuration parameters (SR Configuration) of at least one scheduling request corresponding to each BWP may be obtained; in addition, each SR Configuration can correspond to one or more logical channels. Further, each logical channel may correspond to at most one SR Configuration.

TABLE 1

The terminal device further includes:

an activation unit 43, configured to receive BWP activation information sent from the network side;

As can be seen from the foregoing steps, before receiving BWP activation information sent by the network side, the terminal device can acquire all configuration relationships as shown in table 1, that is, the terminal device can acquire a mapping relationship between a logical channel and configuration parameters of a scheduling request and a mapping relationship between configuration parameters of the scheduling request and BWP in advance.

Further, the terminal device further includes:

a processing unit 44, configured to determine configuration parameters of a scheduling request corresponding to a second BWP, based on the activated second BWP indicated in the BWP activation information and the configuration parameters of at least one scheduling request configured for each BWP; and determining a logical channel corresponding to the configuration parameters of the scheduling request of the second BWP based on the configuration parameters of the scheduling request of the second BWP.

According to the foregoing embodiments, it can be seen that the terminal device is configured with a plurality of BWPs, and for a certain BWP, a plurality of SR configurations are configured; for a certain active BWP, the network configures the mapping relationship from the logical channel to the SR configuration for the terminal, where the active BWP is the BWP for the terminal to receive and transmit data at the current time.

TABLE 2

Further, the terminal device further includes:

a transmitting unit 45 for transmitting the SR;

correspondingly, the processing unit 44 is configured to, when the report of the scheduling request SR is triggered on the logical channel, select a resource of a corresponding physical uplink channel based on a configuration parameter of the scheduling request mapped by the logical channel corresponding to the second BWP, and send the SR on the selected resource of the physical uplink channel.

Example four,

The present application provides a network device, as shown in fig. 5, including:

a first configuration unit 51 configured to configure at least one bandwidth part BWP for the terminal device;

a second configuration unit 52, configured to configure configuration parameters of at least one scheduling request for each BWP in the at least one BWP; and the configuration parameters of the scheduling request and the logical channel have a mapping relation.

Here, the BWP is a concept of a frequency domain dimension, specifically, one or more BWPs that can be configured for a terminal at the network side (or a specific network device) in the RRC connected state; BWP may mainly include the following three parameters: numeriology: marking a basic parameter set and marking a carrier spacing SCS; a center frequency point and a bandwidth. Wherein the size of the bandwidth is less than or equal to the maximum system bandwidth.

wherein SR-PUCCH-resource index indicates the frequency domain resource of the SR transmitted by the UE, and the following description shows that the field is an integer and the value range is 0-2047; the SR-ConfigIndex indicates the time domain resource of PUCCH for transmitting SR, the value of the resource is an integer and the range is 0-157; dsr-TransMax determines the maximum number of SR transmissions.

It should be noted that, through the foregoing processing, a plurality of BWPs that can be configured for the terminal device, and Configuration parameters (SR Configuration) of at least one scheduling request corresponding to each BWP; in addition, each SR Configuration can correspond to one or more logical channels. Further, each logical channel may correspond to at most one SR Configuration.

For example, referring to table 1, when the network configures the BWP for the terminal, the mapping relationship between SR configuration and LCH in the BWP is configured in advance; such as:

for SR configurations respectively belonging to different BWPs, the network configures mapping relationships between logical channels and these SR configurations in advance, for example, BWP- ｃA has two SR configurations, BWP-B has three SR configurations, and BWP-C has one SR configuration:

TABLE 1

The network device further comprises:

an activation information transmitting unit 53 configured to transmit BWP activation information to the terminal device;

Further, the activation information sending unit is configured to perform one of the following processes:

sending BWP activation information to the terminal equipment through downlink control information;

sending BWP activation information to the terminal equipment through a control unit of a media access control layer;

It can be seen that, by adopting the above-mentioned scheme, multiple BWPs configured by the network for the terminal device can be received, and configuration parameters of multiple corresponding scheduling requests can be configured in each BWP, and a mapping relationship is provided between the configuration parameters of each scheduling request and the logical channel. Therefore, the problem that the SR cannot be correctly sent due to the failure of the mapping relation when the terminal device switches the BWP can be avoided, and the processing efficiency of the system is ensured.

An embodiment of the present invention further provides a hardware composition architecture of a terminal device, as shown in fig. 6, including: at least one processor 61, memory 62, at least one network interface 63. The various components are coupled together by a bus system 64. It will be appreciated that the bus system 64 is used to enable communications among the components. The bus system 64 includes a power bus, a control bus, and a status signal bus in addition to the data bus. For clarity of illustration, however, the various buses are labeled as bus system 64 in fig. 6.

It will be appreciated that the memory 62 in embodiments of the invention may be either volatile memory or nonvolatile memory, or may include both volatile and nonvolatile memory.

In some embodiments, memory 62 stores elements, executable modules or data structures, or a subset thereof, or an expanded set thereof: an operating system 621 and application programs 622.

Wherein the processor 61 is configured to: receiving at least one bandwidth part BWP configured on the network side; receiving configuration parameters of at least one scheduling request configured for each BWP by a network side; and the configuration parameters of the scheduling request and the logical channel have a mapping relation.

Specifically, the terminal device can process the method steps of the first embodiment, which is not described herein again.

wherein, when the processor is configured to run the computer program, the method steps of the second embodiment are executed, which is not described herein again.

In an embodiment of the present invention, a computer storage medium is provided, where computer-executable instructions are stored, and when executed, the computer-executable instructions implement the method steps of the first or second embodiment.

The device according to the embodiment of the present invention may also be stored in a computer-readable storage medium if it is implemented in the form of a software functional module and sold or used as an independent product. Based on such understanding, the technical solutions of the embodiments of the present invention may be essentially implemented or a part contributing to the prior art may be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the methods described in the embodiments of the present invention. And the aforementioned storage medium includes: various media capable of storing program codes, such as a usb disk, a removable hard disk, a Read Only Memory (ROM), a magnetic disk, or an optical disk. Thus, embodiments of the invention are not limited to any specific combination of hardware and software.

Accordingly, an embodiment of the present invention further provides a computer storage medium, in which a computer program is stored, where the computer program is configured to execute the data scheduling method according to the embodiment of the present invention.

Although the preferred embodiments of the present invention have been disclosed for illustrative purposes, those skilled in the art will appreciate that various modifications, additions and substitutions are possible, and that the scope of the present invention is not limited to the embodiments disclosed.

Claims

1. A configuration method of a scheduling request is applied to terminal equipment and comprises the following steps:

receiving at least one bandwidth part BWP configured on the network side;

receiving configuration parameters of at least one scheduling request configured for each BWP by a network side; the configuration parameters of the scheduling request and the logic channel have a mapping relation;

receiving BWP activation information sent by a network side; wherein the BWP activation information is used to deactivate a first BWP currently used by the terminal device and activate a second BWP of at least one BWP configured to the terminal device; the first BWP is different from a second BWP;

determining configuration parameters of a scheduling request corresponding to a second BWP based on configuration parameters of the second BWP indicated to be activated in the BWP activation information and at least one scheduling request configured for each BWP;

and determining a logical channel corresponding to the configuration parameters of the scheduling request of the second BWP based on the configuration parameters of the scheduling request of the second BWP.

2. The method according to claim 1, wherein after determining the logical channel corresponding to the configuration parameter of the scheduling request of the second BWP based on the configuration parameter of the scheduling request of the second BWP, the method further comprises:

3. A configuration method of a scheduling request is applied to network equipment and comprises the following steps:

configuring at least one bandwidth part BWP for the terminal device;

configuring configuration parameters of at least one scheduling request for each of the at least one BWP; the configuration parameters of the scheduling request and the logic channel have a mapping relation;

sending BWP activation information to the terminal device; wherein the BWP activation information is used to deactivate a first BWP currently used by the terminal device and activate a second BWP of at least one BWP configured to the terminal device; the first BWP is different from a second BWP;

enabling the terminal device to determine configuration parameters of a scheduling request corresponding to a second BWP based on the activated second BWP indicated in the BWP activation information and the configuration parameters of at least one scheduling request configured for each BWP; and determining a logical channel corresponding to the configuration parameters of the scheduling request of the second BWP based on the configuration parameters of the scheduling request of the second BWP.

4. The method according to claim 3, wherein said sending BWP activation information to said end device comprises one of:

5. A terminal device, comprising:

a second receiving unit, configured to receive configuration parameters of at least one scheduling request configured for each BWP by the network side; the configuration parameters of the scheduling request and the logic channel have a mapping relation;

an activation unit, configured to receive BWP activation information sent by a network side; wherein the BWP activation information is used to deactivate a first BWP currently used by the terminal device and activate a second BWP of at least one BWP configured to the terminal device; the first BWP is different from a second BWP;

a processing unit, configured to determine configuration parameters of a scheduling request corresponding to a second BWP based on configuration parameters of the second BWP indicated to be activated in the BWP activation information and at least one scheduling request configured for each BWP; and determining a logical channel corresponding to the configuration parameters of the scheduling request of the second BWP based on the configuration parameters of the scheduling request of the second BWP.

6. The terminal device according to claim 5, wherein the terminal device further comprises:

a transmission unit configured to transmit the SR;

correspondingly, the processing unit is configured to, when the report of the scheduling request SR is triggered on the logical channel, select a resource of a corresponding physical uplink channel based on a configuration parameter of the scheduling request mapped by the logical channel corresponding to the second BWP, and send the SR on the selected resource of the physical uplink channel.

7. A network device, comprising:

a second configuration unit, configured to configure configuration parameters of at least one scheduling request for each BWP of the at least one BWP; the configuration parameters of the scheduling request and the logic channel have a mapping relation;

an activation information transmitting unit for transmitting BWP activation information to the terminal device; wherein the BWP activation information is used to deactivate a first BWP currently used by the terminal device and activate a second BWP in at least one BWP configured to the terminal device; the first BWP is different from a second BWP;

8. The network device according to claim 7, wherein the activation information sending unit is configured to perform one of the following processes:

9. A terminal device, comprising: a processor and a memory for storing a computer program capable of running on the processor,

wherein the processor is adapted to perform the steps of the method of any of claims 1-2 when running the computer program.

10. A network device, comprising: a processor and a memory for storing a computer program capable of running on the processor,

wherein the processor is adapted to perform the steps of the method of any of claims 3-4 when running the computer program.

11. A computer storage medium storing computer-executable instructions that, when executed, implement the method steps of any of claims 1-2.

12. A computer storage medium having computer-executable instructions stored thereon that, when executed, implement the method steps of any of claims 3-4.